The social science that studies the choices that individuals, businesses, governments, and societies make as they cope with scarcity and incentives that influence and reconcile those choices.

The study of choices made by individuals and businesses, and the influence of government on those choices.

What to produce?  How to produce it?

We need to study these choices to find out what the individual wants.

The study of the effects on the national and global economy of the choices that individuals, businesses and governments make.

What is the interest rate?  What is the inflation rate?